The Phylogenetic Position of Entoprocta, Ectoprocta, Phoronida, and Brachiopoda1

  title={The Phylogenetic Position of Entoprocta, Ectoprocta, Phoronida, and Brachiopoda1},
  author={Claus Nielsen},
  booktitle={Integrative and comparative biology},
  • C. Nielsen
  • Published in
    Integrative and comparative…
    1 July 2002
  • Biology
Abstract Ectoprocts, phoronids and brachiopods are often dealt with under the heading Tentaculata or Lophophorata, sometimes with entoprocts discussed in the same chapter, for example in Ruppert and Barnes (1994). The Lophophorata is purported to be held together by the presence of a “lophophore,” a mesosomal tentacle crown with an upstream-collecting ciliary band. However, the mesosomal tentacle crown of pterobranchs has upstream-collecting ciliary bands with monociliate cells, similar to… 

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The neuroanatomy of Barentsia discreta (Entoprocta, Coloniales) reveals significant differences between bryozoan and entoproct nervous systems

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The observed partitioning of the body cavity in bryozoans differs from that in phoronids and brachiopods, and contradicts the Lophophorata concept.

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Morphological and molecular affi nities of Phoronida and Brachiopoda

  • Biology
  • 2008
The Phoronida Hatschek, 1888 comprise eleven species assigned to the genera Phoronis Wright, 1856 and Phoronopsis Gilchrist, 1907. They possess characteristic features such as a wormlike body that

Organogenesis during budding and lophophoral morphology of Hislopia malayensis Annandale, 1916 (Bryozoa, Ctenostomata)

Different similarities among bryozoans in the formation of the different organ systems are shown: a two-layered vesicle-like early bud, the ganglion forming as an invagination of the epidermal layer in between the prospective mouth and anal area, the digestive tract mainly forming as a outpocketing of the prospective anal area and the lophophore forming from two lateral anlagen that first fuse on the oral and afterwards on the anal side.

Immunocytochemistry and metamorphic fate of the larval nervous system of Triphyllozoon mucronatum (Ectoprocta: Gymnolaemata: Cheilostomata)

The data show that the larval neuroanatomy and the processes that underlie the reorganization of larval organ systems during metamorphosis may vary much more among lophotrochozoan taxa than previously thought.

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The Lophotrochozoa includes disparate tentacle-bearing sessile protostome animals, which apparently appeared in the Cambrian explosion, but lack an uncontested fossil record. Here we describe

Inter- and intraspecific plasticity in distribution patterns of immunoreactive compounds in actinotroch larvae of Phoronida (Lophotrochozoa)

This work is the first to prove the presence of small cardioactive peptide B in phoronids and is described for two larval stages of Phoronis muelleri in order to contribute to the discussion concerning the evolution of lophotrochozoan nervous systems.

Polyzoa is back: The effect of complete gene sets on the placement of Ectoprocta and Entoprocta.

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Function of lateral cilia in suspension feeding of lophophorates (Brachiopoda, Phoronida, Ectoprocta)

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Tentacle structure and filter-feeding in Crisia eburnea and other cyclostomatous bryozoans, with a review of upstream-collecting mechanisms

The differences in structure and functlon between the tentacles of ectoprocts and those of phoronids, brachiopods and pterobranchs support the idea that the 2 types of tentacle crowns are not homologous.

Structure and Function of Metazoan Ciliary Bands and Their Phylogenetic Significance

The trochaea theory predicts that Porifera and Cnidaria have only monociliate cells and lack ciliary bands used in filter-feeding, and that the gastroneuralian larvae have downstream-collecting ciliated bands with prototroch and metatroch of compound cilia on multiciliate cells.

Redescription of Alcyonidium mytili Dalyell, 1848 (Bryozoa: Ctenostomatida)

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The cyphonautes larva of the marine bryozoan Membranipora membranacea. I: General morphology, body wall, and gut

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The Development of the Brachiopod Crania (Neocrania) anomala (O. F. Müller)and its Phylogenetic Significance

Both groups have originated from a creeping ancestor with a straight gut and the ventral curving of the settling larva and the formation of both valves from dorsal epithelial areas indicate that the brachiopods have a very short ventral side as opposed to the phoronids.

Triploblastic Relationships with Emphasis on the Acoelomates and the Position of Gnathostomulida, Cycliophora, Plathelminthes, and Chaetognatha: A Combined Approach of 18S rDNA Sequences and Morphology

The 18S ribosomal sequence data for 145 terminal taxa and 276 morphological characters coded for 36 supraspeci(cid:142)c taxa were combined in a total evidence regime to determine the most consistent picture of triploblastic relationships for these data.

Triploblastic relationships with emphasis on the acoelomates and the position of Gnathostomulida, Cycliophora, Plathelminthes, and Chaetognatha: a combined approach of 18S rDNA sequences and morphology.

For the first time, a data analysis recognizes a clade of acoelomates, the Platyzoa, which is expanded to include the enigmatic phylum Cycliophora, as sister group to Syndermata.


  • S. Carlson
  • Biology, Environmental Science
    Cladistics : the international journal of the Willi Hennig Society
  • 1995
A phylogenetic analysis of the monophyletic status of the Brachiopoda and phylogenetic relationships within the phylum found that arguments concerning single or multiple origins of a bivalved shell are not relevant to recognizing brachiopods as a clade.